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package com.srcptit.trainning.giangnd.btvn1;

import java.util.Scanner;

/**
 *
 * @author GIANG
 */
public class B1 {
    static boolean ngto(int n) {
		if (n < 2)
			return false;
		for (int i = 2; i <= Math.sqrt(n); i++)
			if (n % i == 0)
				return false;
		return true;
	}

	public static void main(String args[]) {
		Scanner sc = new Scanner(System.in);
		int n;
		System.out.println("n=");
		n = sc.nextInt();
		if (ngto(n))
			System.out.println(n + " la so ng to");
		else
			System.out.println(n + " k la so ng to");
	}
}
